JPWO2016158406A1 - Photosensitive resin composition for thin film transistor, cured film, thin film transistor, liquid crystal display device or organic electroluminescence display device, method for producing cured film, method for producing thin film transistor, and method for producing liquid crystal display device or organic electroluminescence display device - Google Patents

Abstract

An object of the present invention is to provide a photosensitive resin composition for a thin film transistor that can form an insulating layer for a thin film transistor that has an extremely low outgas generated from a cured film and is excellent in driving performance. In order to achieve the above object, the present invention has the following configuration. That is, (A) an alkali-soluble resin having an amide group and / or an imide group, (B) a photosensitive compound, and (C) a photosensitive resin composition for a thin film transistor containing an organic solvent, and the (C) organic solvent Among them, the content of the organic solvent having a nitrogen atom is a photosensitive resin composition for a thin film transistor, which is 1% by mass or less based on the total amount of the organic solvent.

Description

  The present invention relates to a photosensitive resin composition for thin film transistors, a cured film, a thin film transistor, a liquid crystal display device or an organic electroluminescent display device, a method for producing a cured film, a method for producing a thin film transistor, and a method for producing a liquid crystal display device or an organic electroluminescent display device. About.

  2. Description of the Related Art Display devices such as liquid crystal and organic EL are mainly driven by an active matrix driving method in which a thin film transistor (hereinafter sometimes referred to as a TFT) is arranged and driven in each pixel. In general, various insulating layers such as a gate insulating layer and an interlayer insulating layer used in a TFT are manufactured by depositing an inorganic material such as silicon nitride or silicon oxide by a vapor deposition method.

  However, the vapor deposition method has a problem that the vacuum equipment necessary for vapor deposition is very expensive. Furthermore, in order to pattern the deposited inorganic film, complicated steps such as application of resist material, exposure, development, etching of the inorganic material, and removal of the resist material must be performed. In addition, in a flexible display using a plastic substrate that has been actively developed in recent years, there has been a problem that a conventional insulating layer using an inorganic material is easily cracked and has insufficient durability.

  In order to solve such problems, studies have been made on using a photosensitive resin composition, which is an organic material, for the gate insulating layer and the interlayer insulating layer. Since the insulating layer using the photosensitive resin composition does not require an expensive vacuum deposition facility, the manufacturing cost can be reduced. Further, since the insulating layer can be patterned by applying, exposing, and developing a photosensitive resin, a resist material is not required and it can be easily processed. Furthermore, since the film toughness is higher than that of the inorganic film, generation of cracks can be suppressed even when used for a flexible display.

  As a photosensitive resin composition for a TFT insulating layer, for example, a material using a polyimide resin has been proposed from the viewpoint of heat resistance (Patent Documents 1 and 2).

JP-A 64-24231 JP 2011-222787 A

  However, these materials cannot be said to have sufficient performance from the viewpoint of outgas suppression, and there has been a problem that driving performance is reduced by an outgas component generated from the insulating layer after thermosetting. In view of the above problems, an object of the present invention is to provide a photosensitive resin composition for a thin film transistor, in which an outgas generated from a cured film is extremely small and an insulating layer for a thin film transistor excellent in driving performance can be formed.

  The present invention is a photosensitive resin composition for a thin film transistor comprising (A) an alkali-soluble resin having an amide group and / or an imide group, (B) a photosensitive compound, and (C) an organic solvent. It is the photosensitive resin composition for thin film transistors whose content of the organic solvent which has a nitrogen atom in an organic solvent is 1 mass% or less with respect to the organic solvent whole quantity.

  According to the present invention, it is possible to provide a photosensitive resin composition for a thin film transistor that can form an insulating layer for a thin film transistor that has very little outgas generated from a cured film and has excellent driving performance.

It is sectional drawing which shows an example of the thin-film transistor of this invention. It is sectional drawing which shows the other example of the thin-film transistor of this invention. It is sectional drawing of the thin-film transistor as described in the Example of this invention.

  The resin composition for a thin film transistor of the present invention is a photosensitive resin composition for a thin film transistor containing (A) an alkali-soluble resin having an amide group and / or an imide group, (B) a photosensitive compound, and (C) an organic solvent. Yes, in the organic solvent (C), the content of the organic solvent having a nitrogen atom is 1% by mass or less based on the total amount of the organic solvent.

  The photosensitive resin composition for a thin film transistor of the present invention contains (A) an alkali-soluble resin having an amide group and / or an imide group. In the present invention, alkali-soluble means that a solution in which a resin is dissolved in γ-butyrolactone is applied on a silicon wafer and prebaked at 120 ° C. for 4 minutes to form a prebaked film having a thickness of 10 μm ± 0.5 μm. The dissolution rate obtained from the reduction in film thickness when the membrane is immersed in a 2.38 mass% tetramethylammonium hydroxide aqueous solution at 23 ± 1 ° C. for 1 minute and then rinsed with pure water is 50 nm / min or more. Say.

  (A) Examples of the alkali-soluble resin having an amide group and / or an imide group include, but are not limited to, polyimide, polyimide precursor, polybenzoxazole, polybenzoxazole precursor, polyaminoamide, and polyamide. You may contain 2 or more types of these resin. Among these alkali-soluble resins, those having excellent heat resistance and a small amount of outgas at high temperature are preferable. Specifically, at least one alkali-soluble resin selected from polyimides, polyimide precursors, and polybenzoxazole precursors or copolymers thereof are preferable.

  The alkali-soluble resin or copolymer thereof selected from (A) polyimide, polyimide precursor, and polybenzoxazole precursor that can be used as the alkali-soluble resin having an amide group and / or an imide group of the present invention is In order to impart the alkali solubility, it is preferable to have an acidic group in the structural unit of the resin and / or at the end of the main chain. Examples of the acidic group include a carboxyl group, a phenolic hydroxyl group, a sulfonic acid group, and a thiol group. The alkali-soluble resin or copolymer thereof preferably has a fluorine atom. When developing with an alkaline aqueous solution, the alkali-soluble resin or copolymer thereof imparts water repellency to the interface between the film and the substrate, Infiltration can be suppressed. The content of fluorine atoms in the alkali-soluble resin or copolymer thereof is preferably 5% by mass or more from the viewpoint of preventing the penetration of the alkaline aqueous solution into the interface, and 20% by mass or less from the viewpoint of solubility in the alkaline aqueous solution. preferable.

  The polyimide described above preferably has a structural unit represented by the following general formula (1), and the polyimide precursor and the polybenzoxazole precursor preferably have a structural unit represented by the following general formula (2). Two or more of these may be contained, or a resin obtained by copolymerizing the structural unit represented by the general formula (1) and the structural unit represented by the general formula (2) may be used.

In general formula (1), R ¹ represents a 4 to 10 valent organic group, and R ² represents a ² to 8 valent organic group. R ³ and R ⁴ represent a phenolic hydroxyl group, a carboxy group, a sulfonic acid group, or a thiol group, and each may be a single group or a different group. p and q represent the integer of 0-6.

In general formula (2), R ⁵ represents a divalent to octavalent organic group, and R ⁶ represents a divalent to octavalent organic group. R ⁷ and R ⁸ represent a phenolic hydroxyl group, a sulfonic acid group, a thiol group, or COOR ⁹ , and each may be a single one or different ones. R ⁹ represents a hydrogen atom or a monovalent hydrocarbon group having 1 to 20 carbon atoms. r and s represent the integer of 0-6. However, r + s> 0.

  The alkali-soluble resin or copolymer thereof selected from polyimide, polyimide precursor, and polybenzoxazole precursor has a structural unit represented by general formula (1) or (2) in the range of 5 to 100,000. It is preferable. Further, in addition to the structural unit represented by the general formula (1) or (2), another structural unit may be included. In this case, it is preferable that the structural unit represented by the general formula (1) or (2) has 50 mol% or more of the total number of structural units.

In the general formula (1), R ^1- (R ³ ) _p represents a residue of acid dianhydride. R ¹ is a tetravalent to 10-valent organic group, and among them, an organic group having 5 to 40 carbon atoms containing an aromatic ring or a cyclic aliphatic group is preferable.

  Specific examples of the acid dianhydride include pyromellitic dianhydride, 3,3 ′, 4,4′-biphenyltetracarboxylic dianhydride, and 2,3,3 ′, 4′-biphenyltetracarboxylic acid. Acid dianhydride, 2,2 ′, 3,3′-biphenyltetracarboxylic dianhydride, 3,3 ′, 4,4′-benzophenonetetracarboxylic dianhydride, 2,2 ′, 3,3 ′ -Benzophenone tetracarboxylic dianhydride, 2,2-bis (3,4-dicarboxyphenyl) propane dianhydride, 2,2-bis (2,3-dicarboxyphenyl) propane dianhydride, 1,1 -Bis (3,4-dicarboxyphenyl) ethane dianhydride, 1,1-bis (2,3-dicarboxyphenyl) ethane dianhydride, bis (3,4-dicarboxyphenyl) methane dianhydride, Bis (2,3-dicarboxy Enyl) methane dianhydride, bis (3,4-dicarboxyphenyl) ether dianhydride, 1,2,5,6-naphthalenetetracarboxylic dianhydride, 9,9-bis (3,4-dicarboxy) Phenyl) fluorenic dianhydride, 9,9-bis {4- (3,4-dicarboxyphenoxy) phenyl} fluorenic dianhydride, 2,3,6,7-naphthalenetetracarboxylic dianhydride, 2 , 3,5,6-pyridinetetracarboxylic dianhydride, 3,4,9,10-perylenetetracarboxylic dianhydride, 2,2-bis (3,4-dicarboxyphenyl) hexafluoropropane dianhydride And aromatic tetracarboxylic dianhydrides such as acid dianhydrides having the structure shown below, butanetetracarboxylic dianhydride, 1,2,3,4-cyclopentanetetracarboxylic acid And aliphatic tetracarboxylic dianhydrides such as anhydride may be mentioned. Two or more of these may be used.

R ¹⁰ represents an oxygen atom, C (CF ₃ ) ₂ , or C (CH ₃ ) ₂ . R ¹¹ and R ¹² represent a hydrogen atom or a hydroxyl group.

In the general formula (2), R ^5- (R ⁷ ) _r represents an acid residue. R ⁵ is a divalent to octavalent organic group, and among them, an organic group having 5 to 40 carbon atoms containing an aromatic ring or a cyclic aliphatic group is preferable.

  Examples of the acid component include dicarboxylic acids such as terephthalic acid, isophthalic acid, diphenyl ether dicarboxylic acid, bis (carboxyphenyl) hexafluoropropane, biphenyl dicarboxylic acid, benzophenone dicarboxylic acid, and triphenyl dicarboxylic acid. Examples of tetracarboxylic acids such as acid, trimesic acid, diphenyl ether tricarboxylic acid, biphenyl tricarboxylic acid, pyromellitic acid, 3,3 ′, 4,4′-biphenyltetracarboxylic acid, 2,3,3 ′, 4′-biphenyl Tetracarboxylic acid, 2,2 ′, 3,3′-biphenyltetracarboxylic acid, 3,3 ′, 4,4′-benzophenonetetracarboxylic acid, 2,2 ′, 3,3′-benzophenonetetracarboxylic acid, 2 , 2-bis (3,4-dical Xylphenyl) hexafluoropropane, 2,2-bis (2,3-dicarboxyphenyl) hexafluoropropane, 1,1-bis (3,4-dicarboxyphenyl) ethane, 1,1-bis (2,3- Dicarboxyphenyl) ethane, bis (3,4-dicarboxyphenyl) methane, bis (2,3-dicarboxyphenyl) methane, bis (3,4-dicarboxyphenyl) ether, 1,2,5,6- Naphthalenetetracarboxylic acid, 2,3,6,7-naphthalenetetracarboxylic acid, 2,3,5,6-pyridinetetracarboxylic acid, 3,4,9,10-perylenetetracarboxylic acid and the structure shown below Aliphatic tetracarboxylic acids such as aromatic tetracarboxylic acid, butanetetracarboxylic acid, 1,2,3,4-cyclopentanetetracarboxylic acid And the like. Two or more of these may be used.

R ¹⁰ represents an oxygen atom, C (CF ₃ ) ₂ , or C (CH ₃ ) ₂ . R ¹¹ and R ¹² represent a hydrogen atom or a hydroxyl group.

Among these, in tricarboxylic acid and tetracarboxylic acid, one or two carboxyl groups correspond to the R ⁷ group in the general formula (2). Further, dicarboxylic acids, tricarboxylic acids exemplified above, a hydrogen atom of the tetracarboxylic acid of the general formula (2) in the R ⁷ groups, preferably and more preferably those substituted 1-4 with phenolic hydroxyl groups. These acids can be used as they are, or as acid anhydrides and active esters.

R ² — (R ⁴ ) _q of the general formula (1) and R ⁶ — (R ⁸ ) _s of the general formula (2) represent a diamine residue. R ² and R ⁸ are divalent to octavalent organic groups, and among them, an organic group having 5 to 40 carbon atoms containing an aromatic ring or a cyclic aliphatic group is preferable.

  Specific examples of diamines include 3,4'-diaminodiphenyl ether, 4,4'-diaminodiphenyl ether, 3,4'-diaminodiphenylmethane, 4,4'-diaminodiphenylmethane, 1,4-bis (4-amino Phenoxy) benzene, benzidine, m-phenylenediamine, p-phenylenediamine, 1,5-naphthalenediamine, 2,6-naphthalenediamine, bis (4-aminophenoxy) biphenyl, bis {4- (4-aminophenoxy) phenyl } Ether, 1,4-bis (4-aminophenoxy) benzene, 2,2′-dimethyl-4,4′-diaminobiphenyl, 2,2′-diethyl-4,4′-diaminobiphenyl, 3,3 ′ -Dimethyl-4,4'-diaminobiphenyl, 3,3'-diethyl-4,4'-diamy Biphenyl, 2,2 ′, 3,3′-tetramethyl-4,4′-diaminobiphenyl, 3,3 ′, 4,4′-tetramethyl-4,4′-diaminobiphenyl, 2,2′-di (Trifluoromethyl) -4,4′-diaminobiphenyl, 9,9-bis (4-aminophenyl) fluorene, or a compound in which at least a part of hydrogen atoms of these aromatic rings is substituted with an alkyl group or a halogen atom, And aliphatic cyclohexyldiamine, methylenebiscyclohexylamine, and diamine having the structure shown below. Two or more of these may be used.

R ¹⁰ represents an oxygen atom, C (CF ₃ ) ₂ , or C (CH ₃ ) ₂ . R ^{11 to} R ¹⁴ each independently represents a hydrogen atom or a hydroxyl group.

  These diamines can be used as diamines or as corresponding diisocyanate compounds, trimethylsilylated diamines.

  In addition, by sealing the ends of these resins with monoamines having acid groups, acid anhydrides, monocarboxylic acid monoacid chlorides, and monoactive esters, resins having acid groups at the main chain ends can be obtained. .

  Preferred examples of the monoamine having an acidic group include 5-amino-8-hydroxyquinoline, 1-hydroxy-7-aminonaphthalene, 1-hydroxy-6-aminonaphthalene, 1-hydroxy-5-aminonaphthalene, 1-hydroxy. -4-aminonaphthalene, 2-hydroxy-7-aminonaphthalene, 2-hydroxy-6-aminonaphthalene, 2-hydroxy-5-aminonaphthalene, 1-carboxy-7-aminonaphthalene, 1-carboxy-6-aminonaphthalene 1-carboxy-5-aminonaphthalene, 2-carboxy-7-aminonaphthalene, 2-carboxy-6-aminonaphthalene, 2-carboxy-5-aminonaphthalene, 2-aminobenzoic acid, 3-aminobenzoic acid, 4 -Aminobenzoic acid, 4-aminosalicylic acid, 5-amino Salicylic acid, 6-aminosalicylic acid, 3-amino-4,6-dihydroxypyrimidine, 2-aminophenol, 3-aminophenol, 4-aminophenol, 2-aminothiophenol, 3-aminothiophenol, 4-aminothiophenol Etc. Two or more of these may be used.

  Preferred examples of the acid anhydride, acid chloride, and monocarboxylic acid include phthalic anhydride, maleic anhydride, nadic acid anhydride, cyclohexanedicarboxylic acid anhydride, acid anhydrides such as 3-hydroxyphthalic acid anhydride, 3- Carboxyphenol, 4-carboxyphenol, 3-carboxythiophenol, 4-carboxythiophenol, 1-hydroxy-7-carboxynaphthalene, 1-hydroxy-6-carboxynaphthalene, 1-hydroxy-5-carboxynaphthalene, 1-mercapto Monocarboxylic acids such as -7-carboxynaphthalene, 1-mercapto-6-carboxynaphthalene, 1-mercapto-5-carboxynaphthalene, and the like, and monoacid chlorides, terephthalic acid, phthalic acid, maleic acid in which these carboxyl groups are converted to acid chlorides acid, Only one carboxyl group of dicarboxylic acids such as chlorohexanedicarboxylic acid, 1,5-dicarboxynaphthalene, 1,6-dicarboxynaphthalene, 1,7-dicarboxynaphthalene, 2,6-dicarboxynaphthalene is converted to acid chloride. And mono-active esters obtained by reaction of mono-acid chloride with mono-acid chloride and N-hydroxybenzotriazole or N-hydroxy-5-norbornene-2,3-dicarboximide. Two or more of these may be used.

  The content of the end-capping agent such as monoamine, acid anhydride, monocarboxylic acid, monoacid chloride, monoactive ester described above is 2 to 100 mol% in total of the acid component and amine component constituting the resin. 25 mol% is preferred.

The end-capping agent introduced into the resin can be easily detected by the following method. For example, a resin having a terminal blocking agent introduced therein is dissolved in an acidic solution and decomposed into an amine component and an acid component, which are constituent units of the resin, and this is measured by gas chromatography (GC) or NMR measurement. The end capping agent can be easily detected. Apart from this, it is possible to detect the resin into which the end-capping agent has been introduced by directly measuring by pyrolysis gas chromatography (PGC), infrared spectrum and ¹³ C-NMR spectrum.

  The alkali-soluble resin (A) having an amide group and / or an imide group used in the present invention can be synthesized by a known method.

  In the case of polyamic acid or polyamic acid ester, as a production method, for example, a method of reacting a tetracarboxylic dianhydride and a diamine compound at a low temperature, a diester is obtained by tetracarboxylic dianhydride and alcohol, and then an amine and a condensing agent It can be synthesized by a method in which a diester is obtained by reacting in the presence of, a tetracarboxylic dianhydride and an alcohol, and then the remaining dicarboxylic acid is acid chlorideed and reacted with an amine.

  In the case of a polybenzoxazole precursor, the production method can be obtained, for example, by subjecting a bisaminophenol compound and a dicarboxylic acid to a condensation reaction. Specifically, a dehydrating condensing agent such as dicyclohexylcarbodiimide (DCC) is reacted with an acid, and a bisaminophenol compound is added thereto, or a solution of a bisaminophenol compound added with a tertiary amine such as pyridine is added to a dicarboxylic acid. For example, a solution of dichloride is dropped.

  In the case of polyimide, the production method can be obtained, for example, by subjecting the polyamic acid or polyamic acid ester obtained by the above-described method to dehydration and ring closure by heating or chemical treatment such as acid or base.

  The photosensitive resin composition for thin film transistors of the present invention contains (B) a photosensitive compound. The photosensitive compound is a compound whose chemical structure changes in response to ultraviolet rays, and specific examples include a photoacid generator, a photobase generator, and a photoradical generator. Among these, the photoacid generator generates an acid in the light irradiation part and increases the solubility of the light irradiation part in the alkaline aqueous solution, so that a positive pattern in which the light irradiation part dissolves can be obtained. The photobase generator generates a base in the light irradiation part and decreases the solubility of the light irradiation part in the alkaline aqueous solution, so that a negative pattern in which the light irradiation part becomes insoluble can be obtained. The photoradical generator generates radicals in the light irradiation area, and when used in combination with radical reactive compounds such as ethylene double bonds, the light irradiation area is less soluble in an alkaline aqueous solution. A negative pattern that is insolubilized can be obtained.

  Among the exemplified photosensitive compounds (B), a photoacid generator is preferred in that a highly sensitive and high resolution pattern can be easily obtained. Examples of the photoacid generator include quinonediazide compounds, sulfonium salts, phosphonium salts, diazonium salts, and iodonium salts. Among the photoacid generators, the photosensitive compound (B) is more preferably a quinonediazide compound because it is easy to obtain a high-sensitivity and high-resolution pattern without undergoing heat treatment after exposure.

  As the quinonediazide compound, a compound in which a sulfonic acid of naphthoquinonediazidesulfonic acid is bonded to a compound having a phenolic hydroxyl group with an ester is preferable. Examples of the compound having a phenolic hydroxyl group used here include Bis-Z, BisP-EZ, TekP-4HBPA, TrisP-HAP, TrisP-PA, TrisP-SA, TrisOCR-PA, BisOCHP-Z, BisP-MZ, BisP. -PZ, BisP-IPZ, BisOCP-IPZ, BisP-CP, BisRS-2P, BisRS-3P, BisP-OCHP, Methylenetris-FR-CR, BisRS-26X, DML-MBPC, DML-MBOC, DML-OCHP, DML-PCHP, DML-PC, DML-PTBP, DML-34X, DML-EP, DML-POP, dimethylol-BisOC-P, DML-PFP, DML-PSBP, DML-MTrisPC, TriML-P, TriML-3 XL, TML-BP, TML-HQ, TML-pp-BPF, TML-BPA, TMOM-BP, HML-TPPHBA, HML-TPHAP (above, trade name, available from Honshu Chemical Industry Co., Ltd.), BIR- OC, BIP-PC, BIR-PC, BIR-PTBP, BIR-PCHP, BIP-BIOC-F, 4PC, BIR-BIPC-F, TEP-BIP-A, 46DMOC, 46DMOEP, TM-BIP-A (above, Trade name, available from Asahi Organic Materials Co., Ltd.), 2,6-dimethoxymethyl-4-tert-butylphenol, 2,6-dimethoxymethyl-p-cresol, 2,6-diacetoxymethyl-p-cresol , Naphthol, tetrahydroxybenzophenone, gallic acid methyl ester, bisphenol A, bisphenol Nord E, methylene bisphenol, BisP-AP (trade names, available from Honshu Chemical Industry Co.) include compounds such as. Preferable examples of the quinonediazide compound used in the present invention include those in which 4-naphthoquinonediazidesulfonic acid or 5-naphthoquinonediazidesulfonic acid is introduced into the compound having a phenolic hydroxyl group by an ester bond. Other compounds can also be used.

  The 4-naphthoquinonediazide sulfonyl ester compound has absorption in the i-line region of a mercury lamp and is suitable for i-line exposure. The 5-naphthoquinone diazide sulfonyl ester compound has an absorption extending to the g-line region of a mercury lamp and is suitable for g-line exposure. In the present invention, both a 4-naphthoquinone diazide sulfonyl ester compound and a 5-naphthoquinone diazide sulfonyl ester compound can be preferably used, but depending on the wavelength to be exposed, the 4-naphthoquinone diazide sulfonyl ester compound or the 5-naphthoquinone diazide sulfonyl ester compound. Is preferably selected. In addition, a naphthoquinone diazide sulfonyl ester compound in which 4-naphthoquinone diazide sulfonyl group and 5-naphthoquinone diazide sulfonyl group are used in the same molecule can be obtained, or 4-naphthoquinone diazide sulfonyl ester compound and 5-naphthoquinone diazide sulfonyl ester compound. Can also be used in combination.

  More preferably, the quinonediazide compound includes a 4-naphthoquinonediazidesulfonyl ester compound. The quinone diazide structure and sulfonyl ester structure of the 4-naphthoquinone diazide sulfonyl ester compound are more easily thermally decomposed than those of the 5-naphthoquinone diazide sulfonyl ester compound. Therefore, by including a 4-naphthoquinone diazide sulfonyl ester compound, components having low heat resistance are removed from the film in the heat curing step, and the outgas-derived components remaining in the cured film can be easily reduced. As a result, an outgas amount generated from the insulating layer is extremely small, and a thin film transistor having excellent driving performance can be easily provided. (B) The content of the 4-naphthoquinone diazide sulfonyl ester compound in the entire content of the photosensitive compound is preferably 50% by mass or more, more preferably 70% by mass, and still more preferably 100% by mass.

  The naphthoquinone diazide sulfonyl ester compound can be synthesized by an esterification reaction between a compound having a phenolic hydroxyl group and a naphthoquinone diazide sulfonic acid compound, and can be synthesized by a known method. By using these naphthoquinone diazide sulfonyl ester compounds, the resolution, sensitivity, and remaining film ratio are further improved.

  The content of the photosensitive compound (B) used in the present invention is preferably 0.1 parts by mass or more, more preferably 100 parts by mass of the alkali-soluble resin (A) having an amide group and / or an imide group. 1 mass part or more, More preferably, it is 2 mass parts or more, Preferably it is 20 mass parts or less, More preferably, it is 14 mass parts or less, More preferably, it is 10 mass parts or less. By setting it as 0.1 mass part or more, it becomes easy to form a pattern, and it becomes easy to suppress the outgas amount derived from a photosensitive compound by setting it as 20 mass parts or less.

  The photosensitive resin composition for thin film transistors of the present invention contains (C) an organic solvent. The organic solvent may be a single solvent or a mixed solvent of two or more, but it is essential that the content of the organic solvent having a nitrogen atom is 1% by mass or less based on the total amount of the organic solvent.

  As a result of intensive studies, the inventors have determined that the organic solvent having a nitrogen atom has an affinity for (A) an amide group and / or an imide group contained in the resin skeleton of the alkali-soluble resin having an amide group and / or an imide group. It was found that the organic solvent is difficult to remove in the thermosetting process even if it is contained in a small amount because the organic solvent remains in the insulating layer after curing, and the driving performance of the thin film transistor is lowered particularly at high temperatures. .

  Examples of the organic solvent having a nitrogen atom include those having a functional group such as an amide group, a urethane group, and a urea group. Specific examples include 2-pyrrolidone, N-methyl-2-pyrrolidone, and N-ethyl-2. -Pyrrolidone, N-propyl-2-pyrrolidone, N-butyl-2-pyrrolidone, N-cyclohexyl-2-pyrrolidone, N- (2-hydroxyethyl) -2-pyrrolidone, N-phenyl-2-pyrrolidone, N- Vinyl-2-pyrrolidone, N, N′-dimethylpropyleneurea, 1,3-dimethyl-2-imidazolidinone, 2-piperidone, ε-caprolactam, N, N-dimethylformamide, N, N-diethylformamide, N , N-dimethylacetamide, N, N-diethylacetamide, N, N-dimethylmethoxyacetamide, N, N-dimethyl Isobutyramide, N, N-dimethylmethoxyethylamide, 3-methoxy-N, N-dimethylpropionamide, 3-butoxy-N, N-dimethylpropionamide, acetamide, benzamide, naphthamide, isophthalamide, terephthalamide, nicotinamide , Isonicotinamide, formamide, propionamide, butyramide, isobutyramide, oxamide, benzylamide, triacetamide, dibenzamide, tribenzamide, urea, butylurea, dibutylurea, 1,3-dimethylurea, 1,3-diethylurea , Glutaramide, butanediamide, hexanediamide, 1,3-dimethyl-2-imidazolidinone, ethyl N-methylcarbamate, urea, butylurea, dibutylurea, 1,3-dimethylurea, 1,3 Diethyl urea, N, N'-dimethyl propylene urea, methoxy -N, N-dimethyl propionamide, butoxy -N, N-dimethyl propionamide, and the like can be given their derivatives. Any of the organic solvents having a nitrogen atom is highly polar, and (A) the alkali-soluble resin having an amide group and / or an imide group has high solubility, and thus has been suitably used as an organic solvent for these resins. However, in the insulating layer application of the thin film transistor of the present invention, it has been found that the organic solvent having a nitrogen atom remains in the insulating layer after curing, even when thermally cured at a temperature higher than the boiling point of the solvent. And it discovered that this trace amount residual solvent reduced the drive performance of a thin-film transistor. Therefore, in this invention, it is essential that content of the organic solvent which has a nitrogen atom is 1 mass% or less with respect to the organic solvent whole quantity.

  In the organic solvent (C), the content of the organic solvent having a nitrogen atom is preferably 0.01% by mass or more, more preferably 0.05% by mass or more, and 1% by mass or less, based on the total amount of the organic solvent. Is preferably 0.5% by mass or less, more preferably 0.3% by mass or less. By setting the content to 0.01% by mass or more, even when the photosensitive resin composition for a thin film transistor is stored at a low temperature of −10 ° C. or less for a long period of time, the precipitation of foreign matters is suppressed, and the occurrence of defective characteristics of the insulating film derived from the foreign matters is generated. Can be reduced. The term “foreign matter” as used herein refers to organic fine particles generated by aggregation and insolubilization of a part of a photosensitive resin composition component dissolved in an organic solvent, in particular, (A) an alkali-soluble resin having an amide group and / or an imide group. Refers to that. The organic solvent having a nitrogen atom has a very high affinity with (A) the amide group and / or imide group contained in the resin skeleton of the alkali-soluble resin having an amide group and / or an imide group. By containing a very small amount of an organic solvent having a nitrogen atom within a range where the driving performance of the thin film transistor is not deteriorated, it is considered that aggregation of the resin component is suppressed even when stored for a long time at a low temperature.

  Among organic solvents having a nitrogen atom, N-methyl-2-pyrrolidone, N-ethyl-2-pyrrolidone, N, N-dimethylformamide, N, N- Examples thereof include diethylformamide, N, N-dimethylacetamide, N, N-diethylacetamide, 1,3-dimethyl-2-imidazolidinone, and N, N-dimethylisobutyramide.

Moreover, it is preferable that content of the organic solvent which satisfies following (1) and (2) in the said (C) organic solvent is 80 mass% or more with respect to the organic solvent whole quantity.
(1) Solubility parameter is 8.0 or more and 11.0 or less [unit is (cal / cm ³ ) ^1/2 ]
(2) Organic compound composed of carbon atom, hydrogen atom, and oxygen atom First, the organic solvent having the solubility parameter of 8.0 to 11.0, which is the first requirement of the organic solvent, is described. To do. The solubility parameter here is used as an indicator of the compatibility and affinity of a plurality of substances, and is defined by the following formula (Formula 1).

δ = (ΔE _V / V ₀ ) ^1/2 ÷ 2.046 [(cal / cm ³ ) ^1/2 ] (Formula 1)
However, ΔE _V [10 ⁶ N · m · mol ⁻¹ ] is the heat of evaporation, and V ₀ [m ³ · mol ⁻¹ ] is the volume per mol. The value of the solubility parameter is smaller as the polarity is lower, and larger as the polarity is higher, for example, n-hexane (7.3), ethanol (12.7), and water (23.4). The difference in solubility parameter between two substances is closely related to the energy required for the two substances to be compatible.The smaller the difference in solubility parameter, the less energy is required for the two substances to be compatible. It will be small. That is, when two substances are present, in general, the smaller the difference in solubility parameter, the higher the affinity and the higher the compatibility.

  The solubility parameter can be determined experimentally or by calculation. Examples of the method for obtaining the solubility parameter by calculation include the method proposed by Fedors et al. (POLYMER ENGINEERING AND SCIENCE, FEBRUARY, 1974, Vol. 14, No. 2, ROBERT F. FEDORS.). In addition, “POLYMER HANDBOOK FORTH EDITION” (WILEY-INTERSCIENCE) describes solubility parameter data of various organic solvents.

  In the present invention, the preferable solubility parameter range is 8.0 or more, more preferably 8.4 or more, and 11.0 or less, more preferably 10.6 or less. By setting it to 8.0 or more, (A) the alkali-soluble resin having an amide group and / or imide group can be sufficiently dissolved, and by selecting an organic solvent satisfying the second requirement of 11.0 or less, photosensitivity can be obtained. The organic solvent is easily removed in the step of thermosetting the functional resin, the organic solvent remaining in the insulating layer after curing can be sufficiently reduced, and excellent driving performance can be easily exhibited. The reason for this will be further described below.

  Generally, when two substances are present, the smaller the difference in solubility parameter, the higher the affinity and the higher the compatibility. Therefore, an organic solvent that is close to the solubility parameter of the resin is preferably selected. The The alkali-soluble resin (A) having an amide group and / or an imide group used in the present invention includes an amide group and / or an imide group in the skeleton, a carboxyl group for imparting alkali solubility, a phenolic hydroxyl group, and a sulfonic acid. Since it contains many polar groups such as groups and thiol groups, it is a highly polar resin and its solubility parameter is high. In the case of a polyimide, polyimide precursor, or polybenzoxazole precursor that can be used as an alkali-soluble resin, the solubility parameter is generally in the range of 12.0 to 16.0. A highly polar solvent having a high affinity with the resin, that is, having a close solubility parameter is excellent in terms of solubility, but it is difficult to remove the organic solvent in the step of thermosetting the photosensitive resin due to its high affinity.

  On the other hand, the solubility parameter of the organic solvent preferably used in the present invention is 11.0 or less, and one that is different from the solubility parameter of the resin is selected. This means that the affinity between the organic solvent and the resin is relatively low, but the low affinity makes it easier for the organic solvent to be removed in the process of thermally curing the photosensitive resin, and the insulating layer after curing. It is possible to sufficiently reduce the remaining organic solvent. Accordingly, a thin film transistor with less outgas generated from the insulating layer and excellent driving performance can be obtained more easily.

  Next, it will be described that the organic solvent, which is the second requirement of the organic solvent, is (2) an organic compound composed of carbon atoms, hydrogen atoms, and oxygen atoms. The organic solvent has an oxygen atom in the molecular structure, and the solvating ability derived from the lone pair of the oxygen atom has (A) an alkali-soluble resin having an amide group and / or an imide group. The solubility of can be increased moderately. On the other hand, examples of the organic solvent having a nitrogen atom in the molecular structure include those having a functional group such as an amide group, a urethane group, and a urea group. These functional groups are amide groups or imides contained in the resin skeleton. Since the affinity with the group is very high, it is difficult to remove the organic solvent in the thermal curing process, and the organic solvent remains in the cured insulating layer, which adversely affects the driving performance of the thin film transistor. Therefore, the organic solvent is preferably an organic compound composed of carbon atoms, hydrogen atoms, and oxygen atoms. Examples of such chemical structures include ether groups, alcohol groups, ester groups, and ketone groups.

Examples of the organic solvent satisfying the above (1) and (2) include ethylene glycol mono-n-butyl ether (9.5, 171 ° C.), diethylene glycol monomethyl ether (10.7, 194 ° C.), diethylene glycol monoethyl ether. (10.4, 202 ° C), diethylene glycol mono-n-butyl ether (9.5, 230 ° C), diethylene glycol dimethyl ether (8.8, 162 ° C), diethylene glycol ethyl methyl ether (8.7, 176 ° C), diethylene glycol diethyl Ether (8.6, 189 ° C), propylene glycol monomethyl ether (10.1, 120 ° C), dipropylene glycol monomethyl ether (9.3, 188 ° C), dipropylene glycol dimethyl ether (8.2, 17) ° C), cyclohexanone (9.9, 156 ° C), cyclopentanone (10.4, 130 ° C), 2-hexanone (8.9, 128 ° C), diacetone alcohol (9.2, 166 ° C), propylene Glycol monomethyl acetate (8.7, 146 ° C.), ethyl lactate (10.0, 155 ° C.), butyl lactate (9.4, 185 ° C.), acetic acid-n-butyl (8.5, 126 ° C.), 3- Examples thereof include methoxybutyl acetate (8.7, 173 ° C.), 3-methyl-3-methylbutyl acetate (9.3, 188 ° C.), ethyl ethoxypropionate (8.9, 166 ° C.) and the like. In addition, the numerical value in the parenthesis after the name of the organic solvent indicates the solubility parameter [unit: (cal / cm ³ ) ^1/2 ], and the boiling point at atmospheric pressure.

  In the organic solvent (C), the content of the organic solvent satisfying the above (1) and (2) is preferably 80% by mass or more, more preferably 90% by mass or more, and still more preferably based on the total amount of the organic solvent. It is 99 mass% or more. By setting it as 80 mass% or more, the organic solvent which remains in the insulating layer after hardening can fully be reduced.

  The organic solvent (C) used in the present invention can be used in combination with an organic solvent other than the organic solvent satisfying the above (1) and (2) according to the purpose.

In the photosensitive resin composition for a thin film transistor of the present invention, it is preferable that the (C) organic solvent satisfying the above (1) and (2) further satisfies the following (3).
(3) By selecting an organic solvent having a boiling point at atmospheric pressure of 100 ° C. or higher and 180 ° C. or lower at atmospheric pressure, poor coating due to too high solvent volatility can be prevented. By selecting an organic solvent having a temperature of 0 ° C. or lower, the organic solvent remaining in the insulating layer after curing can be further reduced.

  The content of the organic solvent (C) used in the present invention is preferably 100 to 2,000 parts by mass with respect to 100 parts by mass of the (A) alkali-soluble resin having an amide group and / or an imide group.

  The organic solvent (C) used in the present invention is not only an organic solvent intentionally added for dissolving the resin composition, but also an organic solvent contained as an impurity in the photosensitive resin composition for thin film transistors. Is also included.

  The photosensitive resin composition for thin film transistors of the present invention can contain a thermal crosslinking agent. The thermal crosslinking agent refers to a compound having in the molecule at least two thermally reactive functional groups such as an alkoxymethyl group, a methylol group, an epoxy group, and an oxetanyl group. The thermal crosslinking agent can crosslink (A) an alkali-soluble resin having an amide group and / or an imide group, or other additive components, and can increase the heat resistance, chemical resistance and hardness of the film after thermosetting.

  Preferred examples of the compound having at least two alkoxymethyl groups or methylol groups include, for example, DML-PC, DML-PEP, DML-OC, DML-OEP, DML-34X, DML-PTBP, DML-PCHP, DML- OCHP, DML-PFP, DML-PSBP, DML-POP, DML-MBOC, DML-MBPC, DML-MTrisPC, DML-BisOC-Z, DML-BisOCHP-Z, DML-BPC, DML-BisOC-P, DMOM- PC, DMOM-PTBP, DMOM-MBPC, TriML-P, TriML-35XL, TML-HQ, TML-BP, TML-pp-BPF, TML-BPE, TML-BPA, TML-BPAF, TML-BPAP, TMOM- BP, TMOM-B E, TMOM-BPA, TMOM-BPAF, TMOM-BPAP, HML-TPPHBA, HML-TPPHAP, HMOM-TPPHBA, HMOM-TPHAP (trade name, manufactured by Honshu Chemical Industry Co., Ltd.), NIKALAC (registered trademark) MX -290, NIKACALAC MX-280, NIKACALAC MX-270, NIKACALAC MX-279, NIKACALAC MW-100LM, NIKACALAC MX-750LM (trade name, manufactured by Sanwa Chemical Co., Ltd.) it can.

  Preferable examples of the compound having at least two epoxy groups include, for example, Epolite 40E, Epolite 100E, Epolite 200E, Epolite 400E, Epolite 70P, Epolite 200P, Epolite 400P, Epolite 1500NP, Epolite 80MF, Epolite 4000, Epolite 3002 (or more , Manufactured by Kyoeisha Chemical Co., Ltd.), Denacol (registered trademark) EX-212L, Denacol EX-214L, Denacol EX-216L, Denacol EX-321L, Denacol EX-850L (above, manufactured by Nagase ChemteX Corporation), Epicort 828, Epicoat 1002, Epicoat 1750, Epicoat 1007, YX8100-BH30, E1256, E4250, E4275 (above, Japan Epoxy Resin Co., Ltd.) ), Epicron (registered trademark) EXA-9583, HP4032, HP7300, N695 (above, manufactured by DIC Corporation), VG3101 (manufactured by Mitsui Chemicals), Tepic (registered trademark) S, Tepic G, Tepic P ( As described above, manufactured by Nissan Chemical Industries, Ltd., Epototo (registered trademark) YH-434L (manufactured by Nippon Steel & Sumikin Chemical Co., Ltd.), EPPN502H, NC3000, NC6000, GAN, GOT (manufactured by Nippon Kayaku Co., Ltd.), Are available from the above companies.

  Preferable examples of the compound having at least two oxetanyl groups include, for example, etanacol (registered trademark) EHO, etanacol OXBP, etanacol OXTP, etanacol OXMA (above, manufactured by Ube Industries, Ltd.), oxetaneated phenol novolak, and the like. .

  Two or more thermal crosslinking agents may be used in combination.

  The content of the thermal crosslinking agent is preferably 0.1 parts by mass or more and 30 parts by mass or less with respect to 100 parts by mass of (A) the alkali-soluble resin having an amide group and / or an imide group. If the content of the thermal crosslinking agent is 0.1 parts by mass or more and 30 parts by mass or less, it becomes easy to increase the chemical resistance and hardness of the film after baking or curing, and the storage stability of the photosensitive resin composition for thin film transistors. It will be easier to improve.

The photosensitive resin composition for a thin film transistor of the present invention preferably further contains (D) an adhesion improver. (D) Adhesion improvers include vinyltrimethoxysilane, vinyltriethoxysilane, epoxycyclohexylethyltrimethoxysilane, 3-glycidoxypropyltrimethoxysilane, 3-glycidoxypropyltriethoxysilane, p-styryltri Silane coupling agents such as methoxysilane, 3-aminopropyltrimethoxysilane, 3-aminopropyltriethoxysilane, N-phenyl-3-aminopropyltrimethoxysilane, titanium chelating agents, aluminum chelating agents, aromatic amine compounds Examples thereof include compounds obtained by reacting an alkoxy group-containing silicon compound. Two or more of these may be contained. (D) By containing an adhesion improving agent, adhesion to an underlying substrate such as a silicon wafer, ITO, SiO ₂ or silicon nitride can be improved when developing a photosensitive resin film. Further, resistance to oxygen plasma and UV ozone treatment used for cleaning or the like can be increased. Further, the driving performance of the thin film transistor can be further improved. Although it is not clear about the mechanism, the adhesion of the base substrate is increased by containing an adhesion improver, and it is difficult for the thin film transistor to peel off even under severe conditions such as high temperature and high humidity. It is presumed that the driving performance is further improved.

  The (D) adhesion improving agent preferably contains a silane coupling agent having a nitrogen atom. This is because the silane coupling agent having a nitrogen atom has high affinity with (A) an alkali-soluble resin having an amide group and / or an imide group, and the adhesion improving effect is particularly high. Examples of the silane coupling agent having a nitrogen atom include 3-aminopropyltrimethoxysilane, 3-aminopropyltriethoxysilane, 3-triethoxysilyl-N- (1,3-dimethylbutylidene) propylamine, and N-phenyl. -3-aminopropyltrimethoxysilane, 3-ureidopropyltriethoxysilane, 3- (2-aminoethyl) aminopropyltrimethoxysilane, 3- (2-aminoethyl) aminopropylmethyldimethoxysilane, and the like. .

  (D) The content of the adhesion improving agent is preferably 0.1 parts by mass or more and 10 parts by mass or less with respect to 100 parts by mass of (A) the alkali-soluble resin having an amide group and / or an imide group.

  The photosensitive resin composition for a thin film transistor of the present invention may contain a surfactant for the purpose of improving the wettability with the substrate or improving the film thickness uniformity of the coating film, if necessary. As the surfactant, commercially available compounds can be used. Specifically, as the silicone-based surfactant, SH series, SD series, ST series of Toray Dow Corning Silicone, BYK series of Big Chemie Japan, Shin-Etsu Silicone The KP series from Nippon Oil & Fats, the TSF series from TOSHIBA Silicone Co., Ltd., etc. are included. As the fluorosurfactants, the “MegaFac (registered trademark)” series from Dainippon Ink Industries, Ltd., Sumitomo 3M Asahi Glass's "Surflon (registered trademark)" series, "Asahi Guard (registered trademark)" series, Shin-Akita Kasei's EF series, Omninova Solution's Polyfox series, etc. And / or methacrylic polymers As it is the surfactant, Kyoeisha Chemical Co. Poly flow series, manufactured by Kusumoto Chemicals, Inc. "DISPARLON (registered trademark)" series, and the like, but each available from companies, but are not limited to.

  The content of the surfactant is preferably 0.001 part by mass or more and 1 part by mass or less with respect to 100 parts by mass of the alkali-soluble resin (A) having an amide group and / or an imide group. By setting it as the above-mentioned range, wettability with a board | substrate and the film thickness uniformity of a coating film can be improved, without producing malfunctions, such as a bubble and a pinhole.

  The photosensitive resin composition for thin film transistors of the present invention may contain a compound having a phenolic hydroxyl group for the purpose of supplementing the alkali developability of the photosensitive resin composition for thin film transistors, if necessary. Examples of the compound having a phenolic hydroxyl group include Bis-Z, BisOC-Z, BisOPP-Z, BisP-CP, Bis26X-Z, BisOTBP-Z, BisOCHP-Z, BisOCR-CP, BisP-MZ, BisP-EZ. Bis26X-CP, BisP-PZ, BisP-IPZ, BisCRIPZ, BisOCP-IPZ, BisOIPP-CP, Bis26X-IPZ, BisOTBP-CP, TekP-4HBPA (Tetrakis P-DO-BPA), TrisPHAP, TrisP-PA, TrisP -PHBA, TrisP-SA, TrisOCR-PA, BisOFP-Z, BisRS-2P, BisPG-26X, BisRS-3P, BisOC-OCHP, BisPC-OCHP, Bis25X-O HP, Bis26X-OCHP, BisOCHP-OC, Bis236T-OCHP, Methylenetris-FR-CR, BisRS-26X, BisRS-OCHP (above, trade name, available from Honshu Chemical Industry Co., Ltd.), BIR-OC, BIP-PCBIR-PC, BIR-PTBP, BIR-PCHP, BIP-BIOC-F, 4PC, BIR-BIPC-F, TEP-BIP-A (above, trade name, available from Asahi Organic Materials Co., Ltd.) 1,4-dihydroxynaphthalene, 1,5-dihydroxynaphthalene, 1,6-dihydroxynaphthalene, 1,7-dihydroxynaphthalene, 2,3-dihydroxynaphthalene, 2,6-dihydroxynaphthalene, 2,7-dihydroxynaphthalene, 2,4-dihydroxyquinoline, 2,6-dihi Rokishikinorin, 2,3-dihydroxy quinoxaline, anthracene -1,2,10- triol, anthracene -1,8,9- triols, such as 8-quinolinol, and the like. By containing these compounds having a phenolic hydroxyl group, the obtained photosensitive resin composition for a thin film transistor hardly dissolves in an alkali developer before exposure, and easily dissolves in an alkali developer upon exposure. There is little film loss due to development, and development is easy in a short time. Therefore, the sensitivity is easily improved.

  The content of such a compound having a phenolic hydroxyl group is preferably 1 part by mass or more and 20 parts by mass or less with respect to 100 parts by mass of (A) an alkali-soluble resin having an amide group and / or an imide group. By setting it as the above-mentioned range, while maintaining high heat resistance, the alkali developability of the photosensitive resin composition for thin film transistors can be improved.

  The photosensitive resin composition for a thin film transistor of the present invention may contain inorganic particles for the purpose of improving the relative dielectric constant of the cured film, improving the hardness, and reducing the coefficient of thermal expansion. Preferable specific examples include silicon oxide, titanium oxide, barium titanate, barium sulfate, barium oxide, zirconium oxide, hafnium oxide, tantalum oxide, tungsten oxide, yttrium oxide, alumina, talc and the like. In particular, for the purpose of improving the relative dielectric constant of the cured film, titanium oxide (εr = 115), zirconium oxide (εr = 30), barium titanate (εr = 400) having a relative dielectric constant (εr) of 20 or more, or Hafnium oxide (εr = 25) is a particularly preferable example, but is not limited thereto. The primary particle diameter of these inorganic particles is preferably 100 nm or less, more preferably 60 nm or less.

  The content of the inorganic particles is preferably 5 parts by mass or more and 500 parts by mass or less with respect to 100 parts by mass of the alkali-soluble resin (A) having an amide group and / or an imide group. By setting it as the above-mentioned range, the effect by addition of the above-mentioned inorganic particles such as improvement of relative dielectric constant can be exhibited while maintaining alkali development performance.

  The photosensitive resin composition for a thin film transistor of the present invention may contain a thermal acid generator. The thermal acid generator generates an acid by heating and promotes the crosslinking reaction of the thermal crosslinker. (A) An unclosed imide ring structure or oxazole ring structure in an alkali-soluble resin having an amide group and / or an imide group When it has, it can accelerate | stimulate these cyclization and can improve the mechanical characteristic of a cured film more.

  The thermal decomposition starting temperature of the thermal acid generator used in the present invention is preferably 50 ° C. to 270 ° C., more preferably 250 ° C. or less. Further, when the photosensitive resin composition for a thin film transistor of the present invention is applied to a substrate and dried (pre-bake: about 70 to 140 ° C.), no acid is generated, and the final heating (cure) after patterning by subsequent exposure and development. : About 100-400 ° C.) is preferable because it can suppress a decrease in sensitivity during development.

  The acid generated from the thermal acid generator used in the present invention is preferably a strong acid. For example, arylsulfonic acid such as p-toluenesulfonic acid and benzenesulfonic acid, methanesulfonic acid, ethanesulfonic acid, propanesulfonic acid, butanesulfonic acid Alkyl sulfonic acids such as haloalkyl sulfonic acids such as trifluoromethyl sulfonic acid are preferred. These are used as salts such as onium salts or as covalently bonded compounds such as imidosulfonates. Two or more of these may be contained.

  The content of the thermal acid generator used in the present invention is preferably 0.01 parts by mass or more and 10 parts by mass or less with respect to 100 parts by mass of (A) the alkali-soluble resin having an amide group and / or an imide group. By setting it as the above-mentioned range, while maintaining high heat resistance, the effect by addition of the above-mentioned thermal acid generator can be expressed.

  Next, a method for producing the photosensitive resin composition for a thin film transistor of the present invention will be described. For example, a thin film transistor is obtained by dissolving the components (A) to (C) and, if necessary, a thermal crosslinking agent, an adhesion improver, a surfactant, a compound having a phenolic hydroxyl group, inorganic particles, a thermal acid generator, and the like. Photosensitive resin composition can be obtained. Examples of the dissolution method include stirring and heating. In the case of heating, the heating temperature is preferably set in a range not impairing the performance of the photosensitive resin composition for thin film transistors, and is usually room temperature to 80 ° C. In addition, the dissolution order of each component is not particularly limited, and for example, there is a method of sequentially dissolving compounds having low solubility. In addition, for components that tend to generate bubbles when stirring and dissolving, such as surfactants and some adhesion improvers, by dissolving other components and adding them last, poor dissolution of other components due to the generation of bubbles Can be prevented.

  The obtained photosensitive resin composition for a thin film transistor is preferably filtered using a filtration filter to remove dust and particles. Examples of the filter pore diameter include, but are not limited to, 0.5 μm, 0.2 μm, 0.1 μm, 0.07 μm, 0.05 μm, and 0.02 μm. Examples of the material for the filter include polypropylene (PP), polyethylene (PE), nylon (NY), polytetrafluoroethylene (PTFE), and polyethylene and nylon are preferable.

  The cured film of the present invention is formed by curing the photosensitive resin composition for a thin film transistor of the present invention. Hereinafter, the manufacturing method of the cured film of this invention is demonstrated in detail.

  The method for producing a cured film of the present invention includes a step of applying the photosensitive resin composition for a thin film transistor of the present invention to form a photosensitive resin film, a step of drying the photosensitive resin film, and exposing the photosensitive resin film. A step, a step of developing the exposed photosensitive resin film, and a step of heat-curing. Details of each step will be described below. In the present invention, among the films formed on the substrate, the film between the application of the photosensitive resin composition for a thin film transistor on the substrate and before the heat curing is referred to as the photosensitive resin film, and the heat curing. The latter film is called a cured film. In addition, the photosensitive resin film from the application of the photosensitive resin composition for thin film transistors to the period before drying may be referred to as a coating film.

  First, a process of applying a photosensitive resin composition for a thin film transistor on a substrate to form a photosensitive resin film will be described. In this step, the photosensitive resin composition for a thin film transistor of the present invention is applied by a spin coating method, a slit coating method, a dip coating method, a spray coating method, a printing method, or the like to obtain a coating film of the photosensitive resin composition for a thin film transistor. . Of these, the slit coat method is preferably used. The slit coating method can be applied with a small amount of coating liquid, and is advantageous for cost reduction. The amount of coating liquid required for the slit coating method is, for example, about 1/5 to 1/10 as compared with the spin coating method. There is no restriction | limiting in particular about the slit nozzle used for application | coating, The thing marketed from the some manufacturer can be used. Specifically, Dainippon Screen Mfg. Co., Ltd. “Linear Coater”, Tokyo Ohka Kogyo Co., Ltd. “Spinless”, Toray Engineering Co., Ltd. “TS Coater”, Chugai Furnace Industry Co., Ltd. “Table Coater” "CS series" "CL series" manufactured by Tokyo Electron Ltd., "Inline slit coater" manufactured by Thermotronics Trading Co., Ltd., "Head coater HC series" manufactured by Hirata Kiko Co., Ltd., and the like. The coating speed is generally in the range of 10 mm / second to 400 mm / second. The film thickness of the coating film varies depending on the solid content concentration, viscosity, etc. of the photosensitive resin composition for thin film transistors, but usually the film thickness after drying is 0.1 to 10 μm, preferably 0.3 to 5 μm. Applied.

  Prior to application, the substrate on which the photosensitive resin composition for a thin film transistor is applied may be pretreated with the adhesion improving agent described above in advance. For example, a solution obtained by dissolving 0.5-20% by mass of an adhesion improver in a solvent such as isopropanol, ethanol, methanol, water, tetrahydrofuran, propylene glycol monomethyl ether acetate, propylene glycol monomethyl ether, ethyl lactate, diethyl adipate, etc. And a method of treating the substrate surface. Examples of the substrate surface treatment method include spin coating, slit die coating, bar coating, dip coating, spray coating, and steam treatment.

  Next, the step of drying the coating film, that is, the photosensitive resin film will be described. In this step, after the photosensitive resin composition for thin film transistors is applied, the coating film is dried. Drying in this step represents vacuum drying or heat drying. Both vacuum drying and heat drying may be performed, or only one of them may be performed.

  First, vacuum drying will be described. In vacuum drying, for example, a substrate on which a coating film is formed is placed on proxy pins arranged in a vacuum chamber, and the coating film is dried by reducing the pressure in the vacuum chamber. At this time, if the distance between the substrate and the vacuum chamber top plate is large, the air located between the substrate and the vacuum chamber top plate flows in a large amount along with the reduced pressure drying, and it becomes easy to generate moire. Therefore, it is preferable to adjust the proxy pin height so as to narrow the interval. The distance between the substrate and the vacuum chamber top is preferably about 2 to 20 mm, more preferably 2 to 10 mm.

  The vacuum drying speed depends on the vacuum chamber volume, the vacuum pump capacity, the pipe diameter between the chamber and the pump, etc., for example, under conditions where the pressure in the vacuum chamber is reduced to 40 Pa after 60 seconds in the absence of a coating substrate. Set and used. The general vacuum drying time is often about 30 to 100 seconds, and the ultimate pressure in the vacuum chamber at the end of the vacuum drying is usually 100 Pa or less with the coated substrate. By setting the ultimate pressure to 100 Pa or less, the coating film surface can be brought into a dry state without stickiness, whereby surface contamination and generation of particles can be suppressed in subsequent substrate transport.

  Next, heat drying will be described. This process is also called pre-baking. Drying uses a hot plate, oven, infrared rays and the like. When a hot plate is used, the coating film is heated directly on the plate or on a jig such as a proxy pin installed on the plate. As the material of the proxy pin, there is a metal material such as aluminum or stainless steel, or a synthetic resin such as polyimide resin or “Teflon (registered trademark)”. Any material can be used as long as it has heat resistance. . The height of the proxy pin varies depending on the size of the substrate, the type of coating film, the purpose of heating, etc., but is preferably about 0.1 to 10 mm. The heating temperature varies depending on the type and purpose of the coating film, and it is preferably performed in the range of 50 ° C. to 180 ° C. for 1 minute to several hours.

  Next, the process for exposing the photosensitive resin film will be described. In this step, in order to form a pattern from the obtained photosensitive resin film, exposure is performed by irradiating actinic radiation through a mask having a desired pattern on the photosensitive resin film. As the actinic radiation used for exposure, there are ultraviolet rays, visible rays, electron beams, X-rays and the like. In the present invention, it is preferable to use i rays (365 nm), h rays (405 nm), and g rays (436 nm) of a mercury lamp. . When it has positive photosensitivity, the exposed portion is dissolved in the developer. When it has negative photosensitivity, the exposed area is cured and insolubilized in the developer.

  Next, a process for developing the exposed photosensitive resin film will be described. In this step, after exposure, a desired pattern is formed by removing an exposed portion in the case of a positive type and a non-exposed portion in the case of a negative type using a developer. As a developer, in both positive and negative types, tetramethylammonium hydroxide, diethanolamine, diethylaminoethanol, sodium hydroxide, potassium hydroxide, sodium carbonate, potassium carbonate, triethylamine, diethylamine, methylamine, dimethylamine, acetic acid An aqueous solution of an alkaline compound such as dimethylaminoethyl, dimethylaminoethanol, dimethylaminoethyl methacrylate, cyclohexylamine, ethylenediamine, hexamethylenediamine and the like is preferable. In some cases, these alkaline aqueous solutions may contain polar solvents such as N-methyl-2-pyrrolidone, N, N-dimethylformamide, N, N-dimethylacetamide, dimethyl sulfoxide, γ-butyrolactone, dimethylacrylamide, methanol, ethanol, Alcohols such as isopropanol, esters such as ethyl lactate and propylene glycol monomethyl ether acetate, ketones such as cyclopentanone, cyclohexanone, isobutyl ketone, and methyl isobutyl ketone may be added singly or in combination. Good. As a developing method, methods such as spraying, paddle, dipping, and ultrasonic waves are possible.

  Next, it is preferable to rinse the pattern formed by development with distilled water. Here, alcohols such as ethanol and isopropyl alcohol, and esters such as ethyl lactate and propylene glycol monomethyl ether acetate may be added to distilled water for rinsing treatment.

  Next, the process of heat curing will be described. In this step, components having low heat resistance can be removed by heat curing, so that heat resistance and chemical resistance can be improved. In particular, when the photosensitive resin composition for a thin film transistor of the present invention contains a polyimide precursor, an alkali-soluble resin selected from a polybenzoxazole precursor, a copolymer thereof, or a copolymer of these and a polyimide. In addition, since an imide ring and an oxazole ring can be formed by heat curing, heat resistance and chemical resistance can be improved, and a compound having at least two alkoxymethyl groups, methylol groups, epoxy groups, or oxytanyl groups is included. In this case, the thermal crosslinking reaction can be advanced by heat curing, and the heat resistance and chemical resistance can be improved. This heat curing is carried out for 5 minutes to 5 hours by selecting the temperature and raising the temperature stepwise, or selecting a certain temperature range and continuously raising the temperature. As an example, a method of performing heat treatment at 150 ° C., 250 ° C., and 400 ° C. for 30 minutes each, or linearly raising the temperature from room temperature to 400 ° C. over 2 hours may be mentioned. The heat curing conditions in the present invention are preferably 300 ° C. or higher, more preferably 350 ° C. or higher, and further preferably 360 ° C. or higher in terms of reducing the amount of outgas generated from the cured film. Moreover, 500 degrees C or less is preferable at the point which gives sufficient film toughness to a cured film, and 450 degrees C or less is more preferable.

  In the thin film transistor manufacturing method of the present invention, the cured film obtained by the above method is used for at least one of the gate insulating layer and the interlayer insulating layer of the thin film transistor.

  When the cured film of the present invention is used for a thin film transistor, a very small amount of outgas component causes a deterioration in driving performance of the thin film transistor, so that the amount of outgas released from the insulating layer is preferably small. In this respect, among the outgas components released when the cured film of the present invention is heated at 180 ° C. for 30 minutes, the amount of organic solvent components generated is preferably 1 ppm or less, more preferably 0.5 ppm or less, and even more preferably. Is 0.2 ppm or less. The total amount of outgas components generated is preferably 5 ppm or less, more preferably 4 ppm or less, and even more preferably 3 ppm or less. The type and amount of gas components used are, for example, the purge and trap / GC-MS method, which is adsorbed and trapped by the purge and trap method and detected by gas chromatography mass spectrometry (GC-MS). Can be measured. As a more specific measurement method, the insulating layer is exposed by disassembling and polishing the thin film transistor, the necessary amount of the insulating layer is sampled, heated at 180 ° C. for 30 minutes, and adsorbed and trapped by the purge and trap method. The analyzed components are analyzed using GC-MS, a calibration curve is prepared using n-hexadecane as a standard substance, and the types and generation amounts of gas components can be obtained.

  The thin film transistor of the present invention has the cured film of the present invention on at least one of a gate insulating layer and an interlayer insulating layer. Hereinafter, the thin film transistor of the present invention will be described with reference to the drawings.

  FIG. 1 is a cross-sectional view showing an example of a thin film transistor of the present invention, which has a top gate type structure. A thin film transistor of the present invention illustrated in FIG. 1 includes a buffer layer 2 on a substrate 1, a semiconductor layer 5 having a source region 3 and a drain region 4 formed on the buffer layer 2, a gate insulating layer 6, and a gate insulating layer. A gate electrode 7 and an interlayer insulating layer 8 formed on the layer 6, and a source electrode 9 and a drain electrode 10 formed so as to be electrically connected to the semiconductor layer 5 are provided.

  FIG. 2 is a cross-sectional view showing another example of the thin film transistor of the present invention and has a bottom-gate structure. A thin film transistor of the present invention illustrated in FIG. 2 includes a buffer layer 2 on a substrate 1, a gate electrode 7 formed on the buffer layer 2, a gate insulating layer 6, and a source region formed on the gate insulating layer 6. 3, a semiconductor layer 5 having a drain region 4, an interlayer insulating layer 8, and a source electrode 9 and a drain electrode 10 formed so as to be electrically connected to the semiconductor layer 5.

  In these examples, at least one of the gate insulating layer 6 and the interlayer insulating layer 8 in FIG. 1 and at least one of the gate insulating layer 6 and the interlayer insulating layer 8 in FIG. 2 are the cured films of the present invention. .

  In the thin film transistor of the present invention, by using the cured film of the present invention for at least one of the gate insulating layer and the interlayer insulating layer, a high-temperature or high-vacuum environment can be used in other manufacturing processes of the thin film transistor and subsequent manufacturing processes of the display device. Even in this case, outgas generated from the insulating layer can be sufficiently reduced. By suppressing outgas, it is possible to prevent impurities from being mixed into the semiconductor layer and to provide excellent TFT driving characteristics.

  In the thin film transistor of the present invention, at least one of the gate insulating layer and the interlayer insulating layer is formed by using the photosensitive resin composition for a thin film transistor of the present invention, so that the expensive vacuum deposition required when forming the conventional inorganic insulating layer. Equipment is not required and costs can be reduced. The insulating layer can be patterned by applying, exposing and developing a photosensitive resin composition for a thin film transistor, and can be easily processed without requiring a resist material. Furthermore, since the film toughness is higher than that of the inorganic film, the occurrence of cracks can be suppressed even when a flexible substrate is used.

  The thin film transistor of the present invention has the cured film of the present invention in an interlayer insulating layer, such as a flexible display using a plastic substrate, and the requirement for TFT driving characteristics is particularly severe, and includes silicon nitride, silicon oxide, acid A top gate type in which at least one of silicon nitride is included in the gate insulating layer is preferable. In the top-gate thin film transistor, as illustrated in FIG. 1, the interlayer insulating layer is not in contact with the semiconductor layer, and the gate insulating layer is in contact with the semiconductor layer. Therefore, high TFT driving characteristics can be easily obtained by using an inorganic film for the gate insulating layer. On the other hand, in order to ensure insulation, the interlayer insulating layer is generally formed thicker than the gate insulating layer. By using a thicker interlayer insulating layer as a cured film using the photosensitive resin composition for thin film transistors, high crack resistance can be obtained.

  Hereinafter, components of the thin film transistor of the present invention will be described in detail.

  The substrate used for the thin film transistor of the present invention is not particularly limited as long as the thin film transistor can be formed on the substrate. Examples of the substrate include glass, quartz, silicon, ceramic, and plastic. Examples of plastics include polyimide, polyethylene terephthalate, polybutylene terephthalate, polyethersulfone, and polyethylene naphthalate.

The buffer layer used in the thin film transistor of the present invention serves to flatten the surface while preventing impurities from penetrating from the substrate, and is not particularly limited as long as it exhibits this effect. Examples of the buffer layer include silicon nitride (SiN _x ), silicon oxide (SiO _x ), and silicon oxynitride (SiO _x N _y ). However, the buffer layer is not always necessary and can be omitted.

The semiconductor layer used in the thin film transistor of the present invention is not particularly limited as long as the thin film transistor can be formed on the substrate, and examples thereof include polysilicon, amorphous silicon, oxide semiconductor, and organic semiconductor. Examples of oxide semiconductors include zinc oxide (ZnO), nickel oxide (NiO), tin oxide (SnO ₂ ), titanium oxide (TiO ₂ ), vanadium oxide (VO ₂ ), indium oxide (In ₂ O ₃ ), Examples include strontium titanate (SrTiO ₃ ), InGaZnO, InAlZnO, InSiZnO, InNiZnO, InCuZnO, InHfZnO, and InZnO. Examples of the organic semiconductor include polythiophene, polyacetylene, polyfluorene, polyphenylene vinylene, polypyrrole, polyaniline, tetracene, pentacene, oligothiophene, perylene, heteroacene, phthalocyanine, and phenylene.

In the thin film transistor of the present invention, at least one of the gate insulating layer and the interlayer insulating layer is formed using the photosensitive resin composition for a thin film transistor of the present invention. Therefore, when using the photosensitive resin composition for thin film transistors of the present invention for the interlayer insulating layer, other materials may be used for the gate insulating layer. Moreover, when using the photosensitive resin composition for thin film transistors of this invention for a gate insulating layer, you may use another material for an interlayer insulation layer. Other materials used for the gate insulating layer or the interlayer insulating layer are not particularly limited as long as they can provide necessary insulating characteristics. For example, silicon nitride (SiN _x ), silicon oxide (SiO _x ), silicon oxynitride (SiO _x N _y ) and the like.

  The gate electrode, source electrode, and drain electrode used in the thin film transistor of the present invention are not particularly limited as long as they can provide necessary conductive performance. For example, Cr, Mo, Al, Cu, Ag, Au, Ti, Ta Nb, W, Fe, Ni, Co, Rh, Nd, Pb, and the like, and alloys or silicides containing these metals can be used. In addition, a conductive material such as ITO or IZO can be used.

  The method for producing a thin film transistor of the present invention includes the method for producing a cured film of the present invention. A general method can be used as a method for manufacturing a thin film transistor using the cured film as at least one of a gate insulating layer and an interlayer insulating layer, and is not particularly limited.

  The thin film transistor of the present invention is not particularly limited as to the type of substrate, but is preferably produced on a flexible substrate in which the insulating layer is required to have crack resistance.

  The thin film transistor of the present invention can be suitably used as a liquid crystal display device or an organic electroluminescence display device (organic EL display device). In particular, it can be suitably used as a flexible display device manufactured using a flexible substrate. In addition to the display device, the thin film transistor of the present invention can also be applied to an IC card or an ID tag manufactured using a flexible substrate.

  The liquid crystal display device or organic electroluminescence display device of the present invention includes the thin film transistor of the present invention.

  The manufacturing method of the liquid crystal display device or organic electroluminescence display device of the present invention uses the thin film transistor obtained by the manufacturing method of the thin film transistor of the present invention. As a method for producing a liquid crystal display device using a thin film transistor obtained by the method for producing a thin film transistor of the present invention, a known method described in, for example, JP-A-2014-157204 can be used. As a method for producing an organic electroluminescent display device using a thin film transistor obtained by the method for producing a thin film transistor of the present invention, for example, a known method described in JP-A-2008-40324 can be used.

Hereinafter, the present invention will be described with reference to examples and the like, but the present invention is not limited to these examples. In addition, the photosensitive resin composition for thin film transistors, the cured film, and the thin film transistor in the examples were evaluated by the following methods.
(1) Analysis of outgas from cured film A varnish suitable for each reference example was applied on an 8-inch silicon wafer by spin coating, and prebaked on a hot plate at 120 ° C. for 2 minutes. 2. Developed with 38% TMAH aqueous solution for 60 seconds and rinsed with pure water. Thereafter, the film was cured in an oven at 380 ° C. for 60 minutes under a nitrogen atmosphere to obtain a cured film having a thickness of 1.0 μm.

  10 mg of the obtained cured film was adsorbed and trapped by the purge and trap method. Specifically, the collected cured film was heated at 180 ° C. for 30 minutes using helium as a purge gas, and the desorbed component was collected in an adsorbent (Carbotrap 400).

  The collected components were thermally desorbed at 280 ° C. for 5 minutes, and then a column: DB-5 (manufactured by Agilent, inner diameter: 0.25 mm, length) using a GC-MS apparatus 6890 / 5973N (manufactured by Agilent). : 30 m, film thickness: 1.0 μm), column temperature: 40 to 300 ° C. (temperature increase rate: 8 ° C./min), carrier gas: helium (1.5 mL / min), scan range: m / z 29 to 600 Under the conditions, GC-MS analysis was performed. The amount of gas generated was calculated in terms of n-hexadecane by preparing a calibration curve by performing GC-MS analysis under the same conditions as described above using n-hexadecane as a standard substance.

(2) Characteristic Evaluation of Thin Film Transistor The thin film transistor used in this example is shown in FIG. An aluminum film was formed on a glass substrate 11 having a thickness of 0.7 mm so as to have a thickness of 100 nm by magnetron DC sputtering. Next, after applying a positive resist solution, it was dried on a hot plate at 90 ° C. to form a resist film. Next, after patterning the resist film by exposure and development, aluminum was selectively removed only in a region having no resist pattern using a phosphoric acid etching solution. Next, the resist film was removed using a stripping solution (monoethanolamine / dimethyl sulfoxide = 7/3), washed with pure water, and dried on a hot plate at 100 ° C. for 30 minutes. In this way, the gate electrode 12 was formed. Next, the photosensitive resin composition for thin film transistors according to each reference example was spin-coated and dried on a hot plate at 100 ° C. to prepare a prebaked film having a thickness of 1000 nm. The obtained pre-baked film was developed with a 2.38% TMAH aqueous solution and then rinsed with water. Next, it was cured in an oven at 380 ° C. for 60 minutes under a nitrogen atmosphere. In this manner, a cured film having a thickness of 500 nm was obtained and used as the gate insulating layer 13.

  Next, an a-Si layer (amorphous silicon layer) having a thickness of 250 nm serving as the semiconductor layer 14 and an n + Si layer having a thickness of 50 nm serving as the impurity-added semiconductor layer 15 were sequentially formed by a CVD method (Chemical Vapor Deposition). Next, after applying a positive resist solution, it was dried on a hot plate at 90 ° C. to form a resist film. Next, the resist film was patterned by exposure and development, and then the impurity-added semiconductor layer and the semiconductor layer were selectively removed by dry etching only in a region having no resist pattern. Next, the resist film was removed using a stripping solution (monoethanolamine / dimethyl sulfoxide = 7/3), washed with pure water, and dried on a hot plate at 100 ° C. for 30 minutes. In this way, a patterned semiconductor layer 14 and impurity-doped semiconductor layer 15 were obtained.

  Next, an aluminum film was formed to a thickness of 100 nm by magnetron DC sputtering. Next, after applying a positive resist solution, it was dried on a hot plate at 90 ° C. to form a resist film. Next, after patterning the resist film by exposure and development, aluminum was selectively removed only in a region having no resist pattern using a phosphoric acid etching solution. Thereafter, only the region having no resist pattern was selectively removed by dry etching using sulfur hexafluoride gas. Next, the resist film was removed using a stripping solution (monoethanolamine / dimethyl sulfoxide = 7/3), washed with pure water, and dried on a hot plate at 100 ° C. for 30 minutes. In this way, an aluminum source electrode 16 and a drain electrode 17 having an electrode width (channel width) of 0.2 mm, an electrode interval (channel length) of 20 μm, and a thickness of 100 nm were obtained.

  Next, the photosensitive resin composition for thin film transistors according to each reference example was spin-coated and dried on a hot plate at 100 ° C. to prepare a pre-baked film having a thickness of 1800 nm. The resulting prebaked film was exposed by placing a photomask, developed with a 2.38% TMAH aqueous solution, and then rinsed with water. Next, it was cured in an oven at 380 ° C. for 60 minutes under a nitrogen atmosphere. In this way, an interlayer insulating layer 18 having a thickness of 1000 nm was obtained in such a manner that a part of the source electrode 16 and the drain electrode 17 was exposed.

  As a result, a thin film transistor substrate provided with a gate insulating layer and an interlayer insulating layer using the photosensitive resin composition for thin film transistors was obtained.

  About the produced thin-film transistor substrate, using the semiconductor characteristic evaluation system 4200-SCS type (manufactured by Keithley Instruments Co., Ltd.), the drain current was measured when the gate voltage was swept in the range of −20V to 20V, and the threshold voltage Vth was calculated. . The substrate after measurement was placed on a hot plate heated to 80 ° C. for 100 hours, and then the threshold voltage Vth was calculated in the same manner as described above. The difference in threshold voltage before and after the high temperature degradation test was calculated, and this absolute value was taken as ΔVth.

(3) Foreign substance evaluation of photosensitive resin film 12 inches of the photosensitive resin composition for thin film transistors immediately after filtration according to each reference example using a coating / developing apparatus “CLEAN TRACK ACT-12” manufactured by Tokyo Electron Co., Ltd. It apply | coated on Si wafer and it was made to dry with a hotplate at 100 degreeC for 3 minute (s), and the photosensitive resin film with a film thickness of 1000 nm was obtained. With respect to the obtained photosensitive resin film, the number of foreign matters having a size of 0.27 μm or more was measured with a wafer surface inspection apparatus “WM-10” manufactured by Topcon Corporation. The measurement area was about 201 cm ² inside a circle having a radius of 8 cm from the center of the wafer, and the number of foreign matters per 1 cm ^{2 of} the coating film was determined.

(4) Determination of aging of foreign matter Using a photosensitive resin composition for a thin film transistor stored at -40 ° C. for 90 days after filtration, a photosensitive resin film was prepared by the method described in (3) above, and the foreign matter was evaluated. Carried out.

Synthesis Example 1 Synthesis of hydroxyl group-containing diamine compound 18.3 g (0.05 mol) of 2,2-bis (3-amino-4-hydroxyphenyl) hexafluoropropane (hereinafter referred to as BAHF) was added to 100 mL of acetone and 17 of propylene oxide. It was dissolved in 0.4 g (0.3 mol) and cooled to -15 ° C. A solution prepared by dissolving 20.4 g (0.11 mol) of 3-nitrobenzoyl chloride in 100 mL of acetone was added dropwise thereto. After completion of dropping, the mixture was reacted at −15 ° C. for 4 hours and then returned to room temperature. The precipitated white solid was filtered off and vacuum dried at 50 ° C.

  30 g of the solid was placed in a 300 mL stainless steel autoclave, dispersed in 250 mL of methyl cellosolve, and 2 g of 5% palladium-carbon was added. Hydrogen was introduced here with a balloon and the reduction reaction was carried out at room temperature. After about 2 hours, the reaction was terminated by confirming that the balloons did not squeeze any more. After completion of the reaction, the catalyst was filtered to remove the palladium compound as a catalyst, and the mixture was concentrated with a rotary evaporator to obtain a hydroxyl group-containing diamine compound represented by the following formula.

Synthesis Example 2 Synthesis of Alkali-Soluble Resin (A-1) BAHF 29.3 g (0.08 mol), 1,3-bis (3-aminopropyl) tetramethyldisiloxane 1.24 g (0.005) under a dry nitrogen stream Mol), 3.27 g (0.03 mol) of 3-aminophenol was dissolved in 150 g of N-methyl-2-pyrrolidone (NMP) as a terminal blocking agent. To this, 31.0 g (0.1 mol) of 3,3 ′, 4,4′-diphenyl ether tetracarboxylic dianhydride (hereinafter referred to as ODPA) was added together with 50 g of NMP, stirred at 20 ° C. for 1 hour, then 50 Stir at 4 ° C. for 4 hours. Thereafter, 15 g of xylene was added, and the mixture was stirred at 150 ° C. for 5 hours while azeotropically distilling water with xylene. After stirring, the solution was poured into 3 L of water to collect a white precipitate. The precipitate was collected by filtration, washed 3 times with water, and then dried for 24 hours in a vacuum dryer at 80 ° C. to obtain an alkali-soluble resin (A-1) which was the target polyimide.

Synthesis Example 3 Synthesis of Alkali-Soluble Resin (A-2) 31.0 g (0.10 mol) of ODPA was dissolved in 500 g of NMP under a dry nitrogen stream. Here, 45.35 g (0.075 mol) of the hydroxyl group-containing diamine compound obtained in Synthesis Example 1 and 1.24 g (0.005 mol) of 1,3-bis (3-aminopropyl) tetramethyldisiloxane were mixed with 50 g of NMP. And reacted at 20 ° C. for 1 hour and then at 50 ° C. for 2 hours. Next, 4.36 g (0.04 mol) of 4-aminophenol as an end-capping agent was added together with 5 g of NMP, and reacted at 50 ° C. for 2 hours. Thereafter, a solution obtained by diluting 28.6 g (0.24 mol) of N, N-dimethylformamide dimethylacetal with 50 g of NMP was added dropwise over 10 minutes. After dropping, the mixture was stirred at 50 ° C. for 3 hours. After completion of the stirring, the solution was cooled to room temperature, and then the solution was poured into 3 L of water to obtain a white precipitate. The precipitate was collected by filtration, washed with water three times, and then dried for 24 hours in a vacuum dryer at 80 ° C. to obtain an alkali-soluble resin (A-2) which was the target polyimide precursor.

Synthesis Example 4 Synthesis of Alkali-Soluble Resin (A-3) Under a dry nitrogen stream, 18.3 g (0.05 mol) of BAHF was dissolved in 50 g of NMP and 26.4 g (0.3 mol) of glycidyl methyl ether, and the temperature of the solution was adjusted. Cooled to -15 ° C. 7.4 g (0.025 mol) of diphenyl ether dicarboxylic acid dichloride (manufactured by Nippon Agricultural Chemicals Co., Ltd.) and 5.1 g (0.025 mol) of isophthalic acid chloride (manufactured by Tokyo Chemical Industry Co., Ltd.) were added to γ-butyrolactone (GBL). ) A solution dissolved in 25 g was added dropwise so that the internal temperature did not exceed 0 ° C. After completion of the dropwise addition, stirring was continued for 6 hours at -15 ° C. After completion of the reaction, the solution was poured into 3 L of water containing 10% by mass of methanol to collect a white precipitate. The precipitate was collected by filtration, washed 3 times with water, and then dried for 24 hours in a vacuum dryer at 80 ° C. to obtain an alkali-soluble resin (A-3) which is the target polybenzoxazole precursor.

Synthesis Example 5 Synthesis of quinonediazide compound (B-1) 21.22 g (0.05 mol) of TrisP-PA (trade name, manufactured by Honshu Chemical Industry Co., Ltd.) and 5-naphthoquinonediazidesulfonyl acid chloride 36 under a dry nitrogen stream .27 g (0.135 mol) was dissolved in 450 g of 1,4-dioxane and brought to room temperature. Here, 15.18 g of triethylamine mixed with 50 g of 1,4-dioxane was added dropwise so that the temperature in the system would not be 35 ° C. or higher. It stirred at 30 degreeC after dripping for 2 hours. The triethylamine salt was filtered and the filtrate was poured into water. Thereafter, the deposited precipitate was collected by filtration. This precipitate was dried with a vacuum dryer to obtain a quinonediazide compound (B-1) represented by the following formula.

Synthesis Example 6 Synthesis of quinonediazide compound (B-2) Under a dry nitrogen stream, TrisP-PA (trade name, manufactured by Honshu Chemical Industry Co., Ltd.) 21.22 g (0.05 mol) and 4-naphthoquinonediazidesulfonyl acid chloride 36 .27 g (0.135 mol) was dissolved in 450 g of 1,4-dioxane and brought to room temperature. Here, 15.18 g of triethylamine mixed with 50 g of 1,4-dioxane was added dropwise so that the temperature in the system would not be 35 ° C. or higher. It stirred at 30 degreeC after dripping for 2 hours. The triethylamine salt was filtered and the filtrate was poured into water. Thereafter, the deposited precipitate was collected by filtration. This precipitate was dried with a vacuum dryer to obtain a quinonediazide compound (B-2) represented by the following formula.

Production Example 1
After dissolving 10.0 g of the alkali-soluble resin (A-1) obtained in Synthesis Example 2 and 1.0 g of (B-1) in 40.0 g of propylene glycol monomethyl ether (hereinafter referred to as PGME) as an organic solvent, A 0.2 μm polytetrafluoroethylene filter (manufactured by Sumitomo Electric Industries, Ltd.) was used to obtain a photosensitive resin composition (varnish) A for thin film transistors.

Production Examples 2 to 19
By the method similar to manufacture example 1, the kind and quantity of a compound were as Table 1 and obtained varnish B-S. Table 2 shows the presence or absence of nitrogen atoms and oxygen atoms in the molecular structure, solubility parameters, and boiling points at atmospheric pressure for the organic solvents used in the production examples.

Examples 1-15, Comparative Examples 1-4
Using the varnishes of Production Examples 1 to 19, a cured film was prepared and outgas analysis was performed according to the method described in (1) Outgas analysis from cured film, and also described in (2) Characteristic evaluation of thin film transistor. A thin film transistor was manufactured according to the method described above, and its characteristics were evaluated. The results are shown in Table 3.

  The cured films of Examples 1 to 15 have a total outgas component generation amount of 7 ppm or less and an organic solvent component generation amount of 3 ppm or less, whereas the cured films of Comparative Examples 1 to 4 have a total outgas component generation amount of organic solvent. It can be seen that the amount of components generated is large. In particular, in the cured films of Examples 1 to 4 and 6 to 15, the total amount of outgas components generated was 5 ppm or less, and the amount of organic solvent components generated was 1 ppm or less, resulting in particularly small amounts. In addition, the thin film transistors of Examples 1 to 15 had a small ΔVth, which is an absolute value of the difference between the threshold voltages before and after the high temperature deterioration test, and showed good driving performance as a thin film transistor. On the other hand, it was found that the thin film transistors of Comparative Examples 1 to 4 had a large ΔVth and a large deterioration in driving performance during high temperature driving. This drive performance deterioration is considered to be caused by outgas generated from the cured film. Among them, Example 14 using a 4-naphthoquinonediazide sulfonyl ester compound as a photosensitizer and Example 15 using an adhesion improver resulted in particularly small ΔVth.

  Moreover, Examples 9-13 whose content of the solvent which has a nitrogen atom in a varnish is 0.01 mass% or more and 1.0 mass% or less with respect to the whole organic solvent are long-term storage at -40 degreeC low temperature. After that, there was almost no increase in foreign matter, and the result was good.

1: substrate 2: buffer layer 3: source region 4: drain region 5: semiconductor layer 6: gate insulating layer 7: gate electrode 8: interlayer insulating layer 9: source electrode 10: drain electrode 11: substrate 12: gate electrode 13: Gate insulating layer 14: Semiconductor layer 15: Impurity-added semiconductor layer 16: Source electrode 17: Drain electrode 18: Interlayer insulating layer

Claims (19)

(A) An alkali-soluble resin having an amide group and / or an imide group, (B) a photosensitive compound, and (C) a photosensitive resin composition for a thin film transistor containing an organic solvent, wherein (C) the organic solvent, The photosensitive resin composition for thin-film transistors whose content of the organic solvent which has a nitrogen atom is 1 mass% or less with respect to the organic solvent whole quantity. The photosensitive resin composition for thin film transistors according to claim 1, wherein the content of the organic solvent satisfying the following (1) and (2) in the (C) organic solvent is 80% by mass or more based on the total amount of the organic solvent. object.
(1) Solubility parameter is 8.0 or more and 11.0 or less [unit is (cal / cm ³ ) ^1/2 ]
(2) Organic compounds composed of carbon atoms, hydrogen atoms, and oxygen atoms 3. The photosensitive resin for a thin film transistor according to claim 1, wherein the content of the organic solvent having a nitrogen atom in the (C) organic solvent is 0.01% by mass or more and 1% by mass or less based on the total amount of the organic solvent. Composition. The photosensitive material for a thin film transistor according to claim 1 or 2, wherein the content of the organic solvent having a nitrogen atom in the (C) organic solvent is 0.01% by mass or more and 0.5% by mass or less based on the total amount of the organic solvent. Resin composition. The photosensitive resin composition for thin film transistors according to any one of claims 2 to 4, wherein the organic solvent (C) that satisfies the above (1) and (2) further satisfies the following (3).
(3) Boiling point at atmospheric pressure is 100 ° C or higher and 180 ° C or lower (A) The alkali-soluble resin having an amide group and / or an imide group is at least one alkali-soluble resin selected from polyimide, a polyimide precursor, and a polybenzoxazole precursor, or a copolymer thereof. The photosensitive resin composition for thin-film transistors in any one of Claims 1-5. The photosensitive resin composition for thin-film transistors according to claim 1, wherein the photosensitive compound (B) is a quinonediazide compound. The photosensitive resin composition for thin-film transistors of Claim 7 in which the said quinonediazide compound contains a 4-naphthoquinonediazide sulfonyl ester compound. The content of the photosensitive compound (B) is at least one selected from (A) an alkali-soluble resin having an amide group and / or an imide group selected from a polyimide, a polyimide precursor, and a polybenzoxazole precursor. The photosensitive resin composition for thin film transistors according to any one of claims 1 to 8, which is 0.1 to 20 parts by mass with respect to 100 parts by mass of the alkali-soluble resin. Furthermore, (D) The photosensitive resin composition for thin-film transistors in any one of Claims 1-9 containing an adhesion improvement agent. The photosensitive resin composition for thin film transistors according to claim 10, wherein the (D) adhesion improving agent contains a silane coupling agent having a nitrogen atom. The cured film which hardened | cured the photosensitive resin composition for thin film transistors in any one of Claims 1-11. A thin film transistor comprising the cured film according to claim 12 on at least one of a gate insulating layer and an interlayer insulating layer. A thin film transistor which is a top gate type, having the cured film according to claim 12 in an interlayer insulating layer and having at least one of silicon nitride, silicon oxide, and silicon oxynitride in a gate insulating layer. A liquid crystal display device or an organic electroluminescent display device comprising the thin film transistor according to claim 13 or 14. The process of apply | coating the photosensitive resin composition for thin film transistors in any one of Claims 1-11 to a board | substrate, forming the photosensitive resin film, the process of drying the said photosensitive resin film, and exposing the said photosensitive resin film The manufacturing method of a cured film including the process, the process of developing the exposed photosensitive resin film, and the process of heat-hardening. The method for producing a cured film according to claim 16, wherein the heat curing step is performed at 300 ° C. or higher and 450 ° C. or lower. The manufacturing method of a thin-film transistor using the cured film obtained by the manufacturing method of Claim 16 or 17. The manufacturing method of a liquid crystal display device or an organic electroluminescent display apparatus using the thin-film transistor obtained by the manufacturing method of Claim 18.

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